The present invention relates to new chemical compounds useful in the treatment of glaucoma and other conditions involving elevated intraocular pressure, processes for synthesizing the compounds, pharmaceutical compositions containing the compounds, and methods of treating glaucoma and other conditions involving elevated intraocular pressure with the present compositions.
Compounds having beta-antagonistic properties are also referred to as "beta-adrenoreceptor antagonists" or, more commonly "beta blockers". Some types of beta blockers are known to be effective in lowering intraocular pressure, primarily by decreasing aqueous humor formation. Compounds having alpha-antagonistic properties are commonly referred to as "alpha-antagonists". These compounds are also known to be effective in lowering intraocular pressure.
The use of two or more different types of drugs to lower elevated intraocular pressure has been a common practice, particularly in connection with patients who exhibit severe elevations in intraocular pressure and/or develop a resistance to the intraocular pressure lowering effect of a single drug. This practice has included combination therapy with a beta blocker and an alpha agonist. Reference is made to the following articles for further background in this regard: McGuinness et al., "Timolol and Dipivalyl Epinephrine Combination Therapy", Aust. J. Ophthalmol., Vol. 10, pages 179-182 (1982); and Weineb et al, "Effect of Adding Betaxolol to Dipivefrin Therapy", Am. J. Ophthalmol., Vol. 101, pages 196-198 (1986).